Roll feeder, press system, and hoop material conveyance method

ABSTRACT

A roll feeder is usable to convey a hoop material to a pressing machine. The roll feeder includes a paired first roll and second roll configured to be disposed so as to clamp the hoop material and feed the hoop material along a conveyance direction, a motor configured to drive at least one of the first roll and the second roll, and a controller configured to control drive of the motor. The controller includes a process drive instruction component configured to drive the motor so as to feed the hoop material to a pressing machine side in between one press working and next press working, and a working drive instruction component configured to drive the motor so as to feed the hoop material to the pressing machine side during press working.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a U.S. National stage application of International Application No. PCT/JP2017/003657, filed on Feb. 1, 2017. This U.S. National stage application claims priority under 35 U.S.C. § 119(a) to Japanese Patent Application No. 2016-046057, filed in Japan on Mar. 9, 2016, the entire contents of which are hereby incorporated herein by reference.

BACKGROUND Field of the Invention

The present invention relates to a roll feeder, a press system, and a hoop material conveyance method.

Description of the Related Art

A configuration comprising an uncoiler, a leveler feeder, a pressing machine, and so forth has been disclosed in the past as a system for producing a molded article by pressing a hoop material wound into a coil.

The leveler feeder corrects any winding curl in the hoop material played out from the uncoiler and intermittently supplies the hoop material to the pressing machine at a specific pitch (see, for example, JP-B S63-56004).

During feed in between one press working and the next press working, the hoop material is fed at a height such that there is no contact with the lower die by a hoop guide or the like, and during press working the pass line is lowered until contact is made with the lower die. Since the pass line thus moves downward during press working, tension is generated in the hoop material when the hoop material is clamped by the leveler feeder, and in some cases the pressing can not be performed properly.

For this reason, a conventional leveler feeder is provided with a release means for moving the feed roll and the work rolls away from the hoop material during press working. The leveler feeder has a cylinder device as a release means, and is configured so that a plurality of upper rolls are separated from a plurality of lower rolls so that the hoop material can be moved freely according to height fluctuations during press working.

SUMMARY

However, with JP-B S63-56004, since it is necessary to separate the upper rolls from the lower rolls, a powerful force is needed to move heavy objects including the upper work rolls, which means that a great deal of energy was consumed.

Also, since the release operation is performed so often (dozens of times per minute), the duration of one release operation is very short, so the operating speed increases. Because the operating speed is high and the weight of the object to be moved is heavy, a problem is that vibration and noise are generated during operation.

In view of the problems encountered in the past, it is an object of the present invention to provide a roll feeder, a press system, and a hoop material conveyance method with which energy consumption and the generation of vibration and sound can be reduced.

The roll feeder pertaining to the first aspect is a roll feeder for conveying a hoop material to a pressing machine, comprising a paired first roll and second roll, a motor, and a controller. The paired first roll and second roll are disposed so as to clamp the hoop material, and feed the hoop material in the conveyance direction. The motor drives the first roll and/or the second roll. The controller controls the drive of the motor. The controller has a process drive instruction component and a working drive instruction component. The process drive instruction component drives the motor so as to feed the hoop material to the pressing machine side in between one press working and next press working. The working drive instruction component drives the motor so as to feed the hoop material to the pressing machine side during press working.

Thus, the first roll and/or the second roll is driven by the motor, and the hoop material is fed into the pressing machine side during press working by the pressing machine. This makes it less likely that a change in the pass line due to sinking of the hoop material during press working will subject the hoop material to tension.

That is, the generation of tension in the hoop material during press working can be suppressed by rotating the first roll and/or the second roll without separating the first roll or the second roll from the hoop material.

Therefore, there is no need for a release operation to separate the first roll or the second roll from the hoop material during working, and all that is necessary is to drive the first roll and the second roll, so energy consumption and the generation of vibration and sound can be reduced.

Also, since there is no need to physically move the first roll or the second roll in the direction of separating from the hoop material, the recent demand for higher production speeds can be met.

The roll feeder pertaining to the second aspect is the roll feeder pertaining to the first aspect, wherein the working drive instruction component drives the motor so as to feed the hoop material by a specific amount toward the pressing machine when the slide of the pressing machine is lowered during the press working, and pull back the hoop material by the specific amount from the pressing machine side when the slide is raised during the press working.

Thus pulling back the hoop material by a specific amount from the pressing machine side when the slide is raised allows the hoop material to be returned to its original position when the height of the hoop material during press working has returned to its original position.

Also, returning the hoop material to its original position prevents the occurrence of twisting caused as a result of a mismatch between the position of the pilot pin (discussed below) and the pin hole of the hoop material, so the hoop material can be prevented from rising along with the upper die.

The roll feeder pertaining to the third aspect is the roll feeder pertaining to the second aspect, wherein “during press working” is from when a pilot pin formed on the upper die attached to the slide is inserted into the hoop material until the pilot pin is removed from the hoop material. The working drive instruction component drives the motor so as to feed a specific amount of the hoop material toward the pressing machine from the point when the pilot pin is inserted into the hoop material until the slide reaches bottom dead center, and pull back a specific amount of the hoop material from the pressing machine side by the point when the pilot pin is removed from the hoop material from bottom dead center.

The occurrence of the tension due to lowering can be suppressed by thus feeding a specific amount of hoop material to the pressing machine side from the time when the pilot pin is inserted until the slide reaches bottom dead center.

Also, the pilot pin can be prevented from catching on the hoop material, and the hoop material can be prevented from rising along with the upper die, by pulling back a specific amount of hoop material from the pressing machine side by the time the pilot pin comes out of the positioning hole from bottom dead center.

The roll feeder pertaining to the fourth aspect is the roll feeder pertaining to the second or third aspect, wherein the working drive instruction component stores a working pattern indicating the relation between the position of the slide and the feed amount of the hoop material when the hoop material is fed by the specific amount to the pressing machine side, and the relation between the position of the slide and the pullback amount of the hoop material when the hoop material is pulled back by a specific amount from the pressing machine side. The working drive instruction component also drives the motor so as to feed the hoop material to the pressing machine side and pull it back from the pressing machine side on the basis of the working pattern.

Since the relation between the position of the slide during press working and the feed amount and the pullback amount of the hoop material is thus stored, the working drive instruction component can feed the hoop material to the pressing machine side or pull the hoop material back from the pressing machine side at the appropriate timing on the basis of position information about the slide transmitted from the pressing machine.

The roll feeder pertaining to the fifth aspect is the roll feeder pertaining to any of the first to third aspects, further comprising a tension sensor for sensing the tension of the hoop material. The working drive instruction component controls the motor so as to bring the tension sensed by the tension sensor close to zero when the hoop material is fed toward the pressing machine during press working.

Sensing the tension generated in the hoop material due to the downward movement of the hoop material during press working and driving the motor so as to bring this tension to zero makes it possible to feed the hoop material to the pressing machine side at the appropriate timing in the raising and lowering of the slide.

When pulling back the hoop material from the pressing machine side, the hoop material sags, so no pushing force is generated, and the tension does not become negative. Therefore, during pullback, a predetermined, constant tension that is weak enough not to cause any problems may be applied. That is, when the hoop material is fed to the pressing machine side, the tension may be controlled to be zero, and when the hoop material is pulled back from the pressing machine side, the tension may be controlled to be weak. The phrase “weak tension” encompasses zero.

The roll feeder pertaining to the sixth aspect is the roll feeder pertaining to the fifth aspect, wherein the tension sensor has a torque sensor provided to the axis of the first roll and/or the second roll. The working drive instruction component controls the motor so as to bring the torque sensed by the torque sensor close to zero during press working.

Thus providing a torque sensor and measuring the torque makes it possible to feed the hoop material toward the pressing machine side or to pull back the hoop material from the pressing machine side at the appropriate timing in the raising and lowering of the slide.

The roll feeder pertaining to the seventh aspect is the roll feeder pertaining to any of the first to sixth aspects, further comprising a plurality of first work rolls and a plurality of second work rolls. The first work rolls are disposed on the upstream side of the first roll in the conveyance direction. The second work rolls are disposed on the upstream side of the second roll in the conveyance direction. The first work rolls and the second work rolls are alternately disposed along the conveyance direction.

Thus disposing the plurality of first work rolls and the plurality of second work rolls allows any winding curl in the hoop material to be corrected.

The roll feeder pertaining to the eighth aspect is the roll feeder pertaining to the seventh aspect, wherein the motor drives the plurality of first work rolls and/or the plurality of second work rolls.

Consequently, when the first work rolls or the second work rolls are provided, the first work rolls or the second work rolls can be rotationally driven during press working along with the first roll or the second roll, and the hoop material can be fed to the pressing machine side.

The roll feeder pertaining to the ninth aspect is the roll feeder pertaining to the fourth aspect, comprising a separation component, a measuring roll, and a roll position sensor. The separation component separates the first roll from the second roll. The measuring roll is disposed so as to come into contact with the hoop material and rotates along with the movement of the hoop material. The roll position sensor senses the position of the measuring roll. The controller further has a working pattern generator. The working pattern generator generates a working pattern in which movement of the hoop material is associated with the position of the slide during press working in a state in which the first roll has been separated from the second roll by the separation component, and stores this working pattern in the working drive instruction component.

Consequently, the relation between the position of the slide and the amount of movement of the hoop material during press working in a state in which the first roll and/or the second roll is separated from the hoop material can be found in advance using the die that will be used, and a working pattern can be generated.

Therefore, feeding the hoop material toward the pressing machine side or pulling back the hoop material from the pressing machine side can be performed at the appropriate timing in the raising and lowering of the slide.

The roll feeder pertaining to the tenth aspect is the roll feeder pertaining to the ninth aspect, further comprising a plurality of first work rolls and a plurality of second work rolls. The first work rolls are disposed on the upstream side of the first roll in the conveyance direction. The second work rolls are disposed on the upstream side of the second roll in the conveyance direction. The first work rolls and the second work rolls are alternately disposed along the conveyance direction.

Thus disposing the plurality of first work rolls and the plurality of second work rolls allows any winding curl in the hoop material to be corrected.

The roll feeder pertaining to the eleventh aspect is the roll feeder pertaining to the tenth aspect, wherein the motor drives the plurality of first work rolls and/or the plurality of second work rolls. The separation component separates the plurality of first work rolls from the plurality of second work rolls.

Consequently, when the first work rolls or the second work rolls are provided, the relation between the position of the slide and the amount of movement of the hoop material during press working in a state in which the first roll and/or the second roll and the plurality of first work rolls and/or the plurality of second work rolls are separated from the hoop material can be found in advance, and a working pattern can be generated.

The press system pertaining to the twelfth aspect comprises a pressing machine and a roll feeder. The pressing machine performs press working of a hoop material. The roll feeder has a paired first roll and second roll, a motor, and a controller. The paired first roll and second roll are disposed so as to clamp the hoop material, and feed the hoop material in a conveyance direction. The motor drives the first roll and/or the second roll. The controller controls the drive of the motor. The controller has a process drive instruction component and a working drive instruction component. The process drive instruction component drives the motor so as to feed the hoop material to the pressing machine side in between one press working and next press working. The working drive instruction component drives the motor so as to feed the hoop material to the pressing machine side during press working.

Consequently, it is not necessary to perform a release operation for separating the first roll or the second roll from the hoop material during working, and it is only necessary to drive the first roll and/or the second roll, so energy consumption and the generation of vibration and sound can be reduced.

Also, since there is no need to physically move the first roll or the second roll in the direction of separating the first roll or the second roll, the recent demand for higher production speeds can be met.

The hoop material conveyance method pertaining to the thirteenth aspect is a hoop material conveyance method for conveying a hoop material to a pressing machine, comprising a process drive step and a working drive step. The process drive step involves driving a first roll and/or a second roll with a motor as a drive source, and feeding the hoop material to the pressing machine side in between one press working and next press working. The working drive step involves driving the motor so as to feed the hoop material to the pressing machine side during press working.

Consequently, there is no need to perform a release operation for separating the first roll or the second roll from the hoop material during working, and it is only necessary to drive the first roll and/or the second roll, so energy consumption and the generation of vibration and sound can be reduced.

Also, since there is no need to physically move the first roll or the second roll in the direction of separating the first roll or the second roll, the recent demand for higher production speeds can be met.

The present invention provides a roll feeder, a press system, and a hoop material conveyance method with which energy consumption and the generation of vibration and sound can be reduced.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a simplified diagram of the configuration of the press system in an embodiment of the present invention;

FIG. 2 is an oblique view of the configuration of the rolls in the leveler feeder in FIG. 1;

FIG. 3 is a simplified front view of the state when a die is disposed at top dead center in the pressing machine in FIG. 1;

FIG. 4 shows the state in FIG. 3 as viewed from the downstream side in the conveyance direction;

FIG. 5 is a simplified front view of the state when a die is disposed at bottom dead center in the pressing machine in FIG. 1;

FIG. 6 shows the slide motion in the press system in FIG. 1;

FIG. 7A shows the state when the upper die has reached bottom dead center in the press system in FIG. 1, and FIG. 7B shows the state when the pilot pin has been removed from the hoop material in the press system in FIG. 1;

FIG. 8 is a simplified diagram of the state during working pattern generation operation in the press system in FIG. 1;

FIG. 9 is a flowchart of the operation of the press system in FIG. 1;

FIG. 10A is a simplified front view of the working feed operation, which is part of the working drive operation in the press system in FIG. 1, FIG. 10B is a simplified front view the working return operation, which is part of the working drive operation in the press system in FIG. 1, and FIG. 10C is a simplified front view of the process drive operation (process feed operation) in the press system in FIG. 1;

FIG. 11 is a simplified diagram of the configuration of the press system in a modification example of an embodiment of the present invention;

FIG. 12 is a simplified diagram of the configuration of the press system in a modification example of an embodiment of the present invention; and

FIG. 13 is a simplified diagram of the configuration of the press system in a modification example of an embodiment of the present invention.

DETAILED DESCRIPTION OF EMBODIMENT(S)

A press system comprising the roll feeder of an embodiment of the present invention will now be described through reference to the drawings.

1. Configuration 1-1. Overview of Press System 1

FIG. 1 is a simplified diagram of the configuration of the press system 1 in this embodiment.

The press system 1 in this embodiment is a system for press working a hoop material 6.

As shown in FIG. 1, the press system 1 comprises a leveler feeder 2, a pressing machine 3, an uncoiler 4, and an operation component 5. The hoop material 6 is wound into a coil and attached to the uncoiler 4.

The uncoiler 4 feeds the hoop material 6 (such as a steel sheet wound into a coil) to the leveler feeder 2 while unwinding it.

The leveler feeder 2 corrects winding curl and the like in the hoop material 6 supplied from a receiver port 2 a. The hoop material 6 is supplied from the uncoiler 4 to the receiver port 2 a of the leveler feeder 2.

A die 10 is attached to the pressing machine 3, and the pressing machine 3 presses the hoop material 6 fed from the leveler feeder 2.

The downstream side in the conveyance direction of the hoop material 6 is labeled X, and the upstream side is labeled Y.

An operation by an operator is inputted to an operation component 5. An instruction is inputted to the feeder controller 29 of the leveler feeder 2, the press controller 39 of the pressing machine 3, and the controller (not shown) of the uncoiler 4 as a result of operator input to the operation component 5, and the press system 1 manufactures a product, etc.

1-2. Pressing Machine

The pressing machine 3 is disposed on the downstream side of the leveler feeder 2 and comprises a bed 31, uprights 32, a bolster 33, a crown 34, a slide 35, a slide driver 36, a crank angle sensor 38, and a press controller 39.

The bed 31 constitutes the base of the pressing machine 3. The bolster 33 is fixed on the bed 31. The uprights 32 are columnar members, and four of them are disposed on the bed 31.

The crown 34 is supported above by the four uprights 32. The slide 35 is suspended below the crown 34.

The slide driver 36 is provided to the crown 34, and moves the slide 35 up and down. The slide 35 moves in the up and down direction so as to guide the uprights 32, which are pillars connecting the bed 31 to the crown 34.

The slide driver 36 has a crank 361 and a connecting rod 362. The crank 361 is disposed in the crown 34 and is rotated by a drive mechanism (not shown). One end of the connecting rod 362 is coupled by a pin in a position that is eccentric to the rotational center of the crank 361. The other end of the connecting rod 362 is connected to the slide 35 by a pin. With this configuration, the slide 35 moves up and down when the crank 361 is rotated. Also, the position of the slide 35 is uniquely decided by deciding the rotational angle of the crank 361.

The crank angle sensor 38 is an encoder or the like, and senses the rotational angle of the crank 361.

The press controller 39 controls the drive mechanism that drives the slide driver 36, and causes the slide 35 to move up and down to perform pressing.

1-3. Leveler Feeder

The leveler feeder 2 corrects any winding curl in the hoop material 6, and feeds the hoop material 6 to the pressing machine 3.

The leveler feeder 2 has a plurality of upper work rolls 21, a plurality of lower work rolls 22, an upper feed roll 23, a lower feed roll 24, a servo motor 25, a servo motor encoder 26, a separation cylinder 27, a movement sensor 28, and a feeder controller 29.

Here, the leveler feeder 2 in this embodiment performs two general types of operation for driving the servo motor 25 (discussed below) to feed the hoop material 6 to the pressing machine 3 side during product manufacture: a process drive operation and a working drive operation.

The process drive operation (also referred to as a process feed operation) is an operation in which the hoop material 6 is fed a distance equal to one process in order to perform pressing between the upper die 11 and the lower die 12 in the next process after performing pressing the hoop material 6 between the upper die 11 and the lower die 12. In the process drive operation, the servo motor 25 is driven on the basis of a process pattern 61 a (discussed below).

The working drive operation is performed in order to suppress the generation of tension in the hoop material 6 as the pass line moves downward along with the downward movement of the die 10 during press working. The working drive operation will be discussed in detail below. The working drive operation is an operation in which the rolls (the lower work rolls 22, the lower feed roll 24, and the upper feed roll 23) are slightly rotated to feed the hoop material 6 and then pull the hoop material 6 back when the hoop material 6 (also referred to as a workpiece) is worked in the vicinity of bottom dead center of the slide 35 in progressive press working. Therefore, the working drive operation includes a working feed operation for feeding the hoop material 6 to the pressing machine 3 side, and a working return operation for pulling back the hoop material 6 from the pressing machine 3 side. In the working drive operation, the servo motor 25 is driven on the basis of a working pattern 62 a (discussed below).

Work Rolls

FIG. 2 is a simplified oblique view of the rollers of the leveler feeder 2. In FIG. 2, the pressing machine is indicated by dotted lines.

Four of the upper work rolls 21 are provided in FIGS. 1 and 2, for example, and three of the lower work rolls 22 are disposed under the upper work rolls 21. The upper work rolls 21 and the lower work rolls 22 are alternately disposed along the conveyance direction, and correct winding curl in the hoop material 6.

The lower work rolls 22 are mechanically linked by a gear or the like (not shown). Power is transmitted from the servo motor 25 to one of the lower work rolls 22 via a speed reducer, causing the lower work rolls 22 to rotate.

The upper work rolls 21 rotate in conjunction with the conveyance of the hoop material 6.

Feed Rolls

The paired upper feed roll 23 and lower feed roll 24 are disposed on the downstream direction X side of the upper work rolls 21 and the lower work rolls 22.

The hoop material 6 is clamped between the upper feed roll 23 and the lower feed roll 24. The lower feed roll 24 and the upper feed roll 23 are linked by a gear or the like (not shown). When power is transmitted from the servo motor 25 via the speed reducer and the lower feed roll 24 rotates, the upper feed roll 23 also rotates. Then, the hoop material 6 clamped between the upper feed roll 23 and the lower feed roll 24 is fed toward the pressing machine 3.

Servo Motor

The drive force of the servo motor 25 is transmitted to the lower feed roll 24 and one lower work roll 22, and the lower feed roll 24 and the lower work roll 22 rotate. The rotation of the lower feed roll 24 causes the upper feed roll 23 linked to the lower feed roll 24 by a gear or the like to rotate. Also, rotation of the one lower work roll 22 causes the plurality of lower work rolls 22 to rotate. The servo motor encoder 26 senses the rotational angle (also referred to as a rotational position) and the rotational angular velocity of the servo motor 25.

Separation Cylinder

When the hoop material 6 placed in the uncoiler 4 is passed to the leveler feeder 2 before manufacture of the product, the separation cylinder 27 separates the upper work rolls 21 and the upper feed roll 23 upward from the lower work rolls 22 and the lower feed roll 24.

The cylinder rod of the separation cylinder 27 is attached to a support 2 b that supports the upper feed roll 23 and the upper work rolls 21. Upward movement of the cylinder rod of the separation cylinder 27 causes the support 2 b to rotate upward around a rotary shaft 2 c (see arrow A).

Movement Sensor

The movement sensor 28 senses the amount by which the rolls are rotated during working drive operation. The movement sensor 28 has a measuring roll 51 and a measuring roll encoder 52. As shown in FIGS. 1 and 2, the measuring roll 51 is pressed against the passed hoop material 6, and rotates along with the movement of the hoop material 6. As shown in FIG. 2, the width of the measuring roll 51 does not need to cover the entire width of the hoop material 6. The measuring roll encoder 52 detects the rotation of the measuring roll 51.

The measuring roll 51 is used to produce, prior to manufacture, the working pattern 62 a (discussed below) that will be used during manufacture.

Prior to manufacture of the product, the lower die 12 and the upper die 11 that will be used for manufacture are placed in the pressing machine 3, and material is passed through the leveler feeder 2 before manufacture of the product, after which the upper feed roll 23 and the upper work rolls 21 are moved upward, and pressing is performed in that state.

During this pressing, the hoop material 6 is pulled into the pressing machine 3 as the pass line moves downward, and the measuring roll 51 rotates along with the movement of the hoop material 6. The amount of hoop material 6 that is drawn into the pressing machine 3 can be sensed by sensing this rotation with the measuring roll encoder 52. The downward movement and pull-in of the pass line will be described below.

Feeder Controller

The feeder controller 29 mainly controls the servo motor 25 on the basis of the crank angle acquired from the crank angle sensor 38 during manufacture of the product based on an instruction from the operator inputted to the operation component 5.

The feeder controller 29 has a working pattern generation instruction component 60, a process drive instruction component 61, a working drive instruction component 62, a first switching component 63, a position comparison component 64, a position controller 65, a speed comparison component 66, a speed controller 67, a current comparison component 68, a current controller 69, a current sensor 70, a position calculator 71, a speed calculator 72, a second switching component 73, and a working pattern generator 74.

The process drive instruction component 61 stores a process pattern 61 a, which is the relation between the crank angle and the position of the hoop material 6 in the process drive operation (also referred to as the relation of the movement amount of the hoop material 6 for each crank angle). On the basis of the process pattern 61 a, the process drive instruction component 61 receives the crank angle from the crank angle sensor 38 and transmits a position instruction to the servo motor 25.

The working drive instruction component 62 stores the working pattern 62 a, which is the relation between the crank angle and the position of the hoop material 6 in the working drive operation (also referred to as the relation of the movement amount of the hoop material 6 for each crank angle). On the basis of the working pattern 62 a, the working drive instruction component 62 receives the crank angle from the crank angle sensor 38 and transmits a position instruction to the servo motor 25.

The working pattern generation instruction component 60 issues an instruction to generate the working pattern 62 a.

The first switching component 63 selectively sends the second switching component 73 a position instruction for each crank angle from the process drive instruction component 61, a position instruction for each crank angle from the working drive instruction component 62, and information about the crank angle from the working pattern generation instruction component 60. More precisely, the first switching component 63 connects a-b for a process drive instruction, connects c-b for a working drive instruction, and connects d-b for a working pattern generation instruction.

The second switching component 73 connects a-b for a process drive instruction or a working drive instruction, and outputs a position instruction for each crank angle from the process drive instruction component 61 or a position instruction for each crank angle from the working drive instruction component 62, to the position comparison component 64.

Also, the second switching component 73 connects a-c for a working pattern generation instruction, and sends the working pattern generator 74 information about the crank angle from the crank angle sensor 38 (also referred to as slide position information).

The position calculator 71 calculates the position of the hoop material 6 (also referred to as the movement amount (feed amount or return amount) of the hoop material 6) from the rotation of the measuring roll encoder 52 during process drive instruction or working drive instruction, and outputs the position signal to the position comparison component 64.

The position comparison component 64 compares the position signal from the position calculator 71 with the position instruction from the process drive instruction component 61 or the working drive instruction component 62, and outputs the difference to the position controller 65.

The position controller 65 generates a speed signal on the basis of the difference transmitted from the position comparison component 64, and transmits the generated speed signal to the speed comparison component 66.

The speed calculator 72 receives the rotational angular velocity of the motor from the servo motor encoder 26, calculates the actual speed of the hoop material 6, and outputs a speed signal to the speed comparison component 66.

The speed comparison component 66 compares the speed signal generated by the position controller 65 with the actual speed information inputted from the speed calculator 72, and transmits the difference to the speed controller 67. Instead of using the actual speed information obtained from the servo motor encoder 26 via the speed calculator 72 as the speed information inputted to the speed comparison component 66, the differentiated value of the position information from the measuring roll encoder 52 may be used as actual speed information.

The speed controller 67 creates a current signal on the basis of the difference transmitted from the speed comparison component 66, and this signal is transmitted to the current comparison component 68.

The current comparison component 68 compares the current signal generated by the speed controller 67 with the information about the current value from the current sensor 70 that senses the current of the servo motor 25, and transmits the difference to the current controller 69.

The current controller 69 generates an appropriate supply current based on the difference, and supplies it to the servo motor 25.

In a working pattern generation operation, the working pattern generator 74 generates the working pattern 62 a in which information about the crank angle (slide position information) received via the working pattern generation instruction component 60 is associated with the pull-in position of the hoop material 6 sensed by the measuring roll 51, and stores this working pattern in the working drive instruction component 62.

The process pattern 61 a stored by the process drive instruction component 61 may be preset and stored for each die 10, or the process pattern 61 a may be produced by performing adjustment in trial pressing for a specific pattern.

1-4. Die

FIG. 3 is a simplified diagram of the die 10 and the area around the hoop material 6 in a state in which the slide 35 is disposed at top dead center. FIG. 4 is a view of FIG. 3 as seen from the downstream direction X side.

The die 10 used for working the product has a plurality of upper dies 11 and a plurality of lower dies 12. Also, a plurality of hoop guides 13 are provided on the bolster 33.

The upper dies 11 are attached to the lower face of the slide 35. The lower dies 12 are fixed on the bolster 33.

The upper dies 11 are disposed along the conveyance direction. The lower dies 12 are also disposed along the conveying direction. One upper die 11 and one lower die 12 are disposed opposite each other vertically. That is, a plurality of pairs of the upper die 11 and the lower die 12 are arranged along the conveyance direction.

The press system 1 in this embodiment is used to perform progressive press working, and a pair of an upper die 11 and a lower die 12 corresponds to one process. Then, the hoop material 6 is fed one process at a time to the downstream direction X side, whereby the product is manufactured.

As shown in FIG. 4, the hoop guides 13 are disposed at both ends in the width direction of the hoop material 6. A groove 13 a is formed on the inside of each hoop guide 13, and the hoop material 6 is held in the up and down direction by fitting the end of the hoop material 6 into the grooves 13 a. Also, the hoop guides 13 are supported by spring elements 14 from below. Presser pins 15 (see FIG. 3) are provided on the lower side of the slide 35 so as to be opposite the hoop guides 13 in the up and down direction. During pressing, the presser pins 15 hold the hoop guides 13 down.

Pilot pins 16 are provided to the upper dies 11, and insertion holes 17 into which the pilot pins 16 are inserted are formed in the lower dies 12.

In progressive production such as with the press system 1 in this embodiment, since the hoop material 6 is pushed in from the upstream side Y to perform the process drive operation (also referred to as process feed operation), it is necessary to ensure that the hoop material 6 has reached a specific position for each process, and the pilot pins 16 are generally used for this.

For example, punches 18 for forming positioning holes in the hoop material 6 are provided on the leftmost upper die 11 corresponding to the first process, and positioning holes 6 a are formed in the hoop material 6 in the first process.

The pilot pins 16 are provided at positions corresponding to the second upper die 11 from the left end corresponding to the second process. The pilot pins 16 are inserted into the positioning holes 6 a formed in the hoop material 6 by the punches 18, thereby positioning the hoop material 6 with respect to the die 10. Providing the pilot pins 16 in the third and subsequent processes allows the position of the die 10 to be lined up with the position of the hoop material 6 in each process.

That is, the spacing L between the punches 18 and the pilot pins 16 becomes the feed amount of the hoop material 6 for one process.

1-5. Downward Movement and Pull-In of the Pass Line

Next, the downward movement of the pass line and the pull-in of the hoop material will be described using the press system 1.

FIG. 5 is a simplified diagram of the state when the slide 35 has descended to bottom dead center. Even in transfer working, generally not only cutting and punching, but also forming such as bending and drawing are performed. Therefore, fluctuation of the feed height (pass line) of the hoop material 6 equivalent to the forming height is inevitable. At top dead center in FIG. 3 (more precisely, in a state in which the slide 35 is disposed at a position high enough that the upper dies 11 do not touch the hoop material 6), the pass line is such that its height above the bolster 33 is indicated by a. In FIG. 3, the height of the nip between the upper feed roll 23 and the lower feed roll 24 corresponding to the hoop material 6 exit from the leveler feeder 2 is set to the same height a (the height of the pass line) to make the system easier to understand.

When the slide 35 descends from the state in FIG. 3 to bottom dead center, the hoop guides 13 are pushed by the presser pins 15 and the height of the pass line is reduced from a to b. That is, the pass line at bottom dead center is lower by a-b than the pass line up until the upper dies 11 touch the hoop material 6. On the other hand, since the height of the lower feed roll 24 remains unchanged at the height a, the hoop material 6 is pulled in slightly in the downstream direction X in the course of the slide 35 reaching bottom dead center, but when the upper work rolls 21, the lower work rolls 22, the upper feed roll 23, the lower feed roll 24, and so on have come to a stop, tension is generated in the hoop material 6.

With the leveler feeder 2 of this embodiment, in this pull-in, the servo motor 25 is controlled to rotate the lower work rolls 22, the upper feed roll 23, and the lower feed roll 24 so as to minimize the generation of tension.

In the following description, saying that the pilot pins 16 are inserted into the positioning holes 6 a of the hoop material 6 or pulled out of the positioning holes 6 a encompasses the insertion or withdrawal of the punches 18 into or from the hoop material 6.

2. Operation

Next, the operation of the leveler feeder 2 in this embodiment will be described, and an example of the hoop material conveyance method of the present invention will be discussed at the same time.

2-1. Process Pattern and Working Pattern

First, the relation between the process pattern 61 a, the working pattern 62 a, and slide motion will be described. FIG. 6 is a diagram of slide motion. In FIG. 6, the vertical axis is the slide position, and the horizontal axis is the crank angle.

In the slide motion shown in FIG. 6, a state is shown in which the slide 35 moves up and down according to the crank angle.

As described above, in the process drive operation performed on the basis of the process pattern 61 a shown in FIG. 1, after the hoop material 6 is pressed between the upper dies 11 and the lower dies 12, the hoop material 6 is fed by a distance equal to one process in order to perform pressing between the upper dies 11 and the lower dies 12 in the next process. This process drive operation (process feed operation) may be started after the pilot pins 16 are removed from the hoop material 6 in the course of the slide 35 rising beyond bottom dead center, and must conclude by the time the pilot pins 16 are inserted into the positioning holes 6 a in the hoop material 6 in the course of the slide 35 descending.

In order to prevent the generation of tension, the working feed operation, which is part of the working drive operation performed on the basis of the working pattern 62 a shown in FIG. 1, must be carried out before bottom dead center (θ2) is reached after the pilot pins 16 are inserted into the positioning holes 6 a in the hoop material 6. It is also necessary to pull back the hoop material 6 before the pilot pins 16 are removed from the positioning holes 6 a in the hoop material 6 from bottom dead center.

In view of this, the timing of this switching is based on the slide height at which the pilot pins 16 are inserted into and removed from the positioning holes 6 a. This height is h1 in FIGS. 7A and 7B at the slide position based on bottom dead center. FIG. 7A shows the state when an upper die reaches bottom dead center, and FIG. 7B shows the state when a pilot pin 16 has been removed from a positioning hole 6 a in the hoop material 6. Since h1 is determined for each product and die, this is matched with slide motion, and made to correspond to the crank angle as shown in FIG. 6. The crank angles when the slide height is h1 are indicated by θ1, θ3, and θ4. θ1 indicates when the slide 35 descends and the pilot pins 16 are inserted into the positioning holes 6 a in the hoop material 6. θ3 indicates when the slide 35 ascends and the pilot pins 16 are removed from the positioning holes 6 a in the hoop material 6. θ4 indicates when the pilot pins 16 are inserted into the hoop material 6 in the next cycle after θ3. θ2 is the crank angle at bottom dead center.

A position instruction is transmitted from the process drive instruction component 61, and in the block diagram in FIG. 1, the first switching component 63 is connected a-b from a crank angle of θ3 to θ4. Also, a position instruction is transmitted from the working drive instruction component 62, and the first switching component 63 is connected c-b from θ1 to θ3.

2-2. Working Pattern Generation Operation

When manufacture of a product is started using a new die 10 or hoop material 6, a working pattern generation operation is performed before manufacture of the product is commenced.

The working pattern generation operation is an operation to generate the working pattern 62 a.

First, the hoop material 6 wound into a coil is placed in the uncoiler 4. Also, the die 10 to be used for manufacture is attached to the pressing machine 3.

At the leveler feeder 2, the upper feed roll 23 and the upper work rolls 21 are separated from the lower feed roll 24 and the lower work rolls 22 by the contraction of the separation cylinder 27.

In this way, the hoop material 6 is passed through the receiver port 2 a to the leveler feeder 2 in a separated state.

In this state, the operation of sensing the relation between the position of the hoop material 6 and the crank angle during the working drive operation is carried out when the operator inputs a working pattern generation instruction to the operation component 5.

More precisely, as shown in FIG. 8, in a state in which the upper feed roll 23 and the upper work rolls 21 are separated upward from the hoop material 6, the press controller 39 controls the drive mechanism, the slide 35 moves downward, and pressing is performed between the upper dies 11 and the lower dies 12.

The result of this pressing operation is that the height of the pass line is lowered from a to b, and the hoop material 6 is pulled in. The amount by which the hoop material 6 is pulled in is sensed by the measuring roll 51. As described above, the crank angle information (also referred to as slide position information) from the crank angle sensor 38 is inputted to the working pattern generation instruction component 60, and is outputted to the first switching component 63.

The first switching component 63 makes a d-b connection, and the second switching component 73 makes an a-c connection. Information about the crank angle is then outputted to the working pattern generator 74.

Meanwhile, the amount of movement of the hoop material 6 due to the pull-in sensed by the measuring roll 51 is also outputted to the working pattern generator 74.

The working pattern generator 74 then associates the crank angle information (slide position information) with the movement amount of the hoop material 6, calculates the movement amount for each crank angle, and generates the working pattern 62 a, which is stored in the working drive instruction component 62.

2-3. Press Operation

Next, the pressing operation during product manufacture will be described.

After the working drive pattern generation discussed above, the separation cylinder 27 is extended upon input to the operation component 5 or the like, and the upper work rolls 21 and the upper feed roll 23 come into contact with the hoop material 6.

FIG. 9 is a flowchart of the operation of the leveler feeder 2 in this embodiment.

Assuming a start from a state in which the hoop material 6 is passed between the upper dies 11 and the lower dies 12 in the first process, since process feed has not been performed, the feeder controller 29 waits for the crank angle θ1 to be detected in step S11. That is, the feeder controller 29 receives a crank angle signal from the crank angle sensor 38 and detects that the crank angle has reached θ1 (see FIG. 6).

Next, in step S12, an instruction for working feed is issued by the working drive instruction component 62 of the feeder controller 29. The feeder controller 29 controls the servo motor 25 on the basis of the working pattern 62 a (see FIG. 1), and feeds the hoop material 6 toward the pressing machine 3 side as the slide 35 descends, as shown in FIG. 10A. Here, feed of the hoop material 6 in the working feed operation is performed from the point (θ1) when the pilot pins 16 are inserted into the positioning holes 6 a of the hoop material 6 up until bottom dead center (θ2).

When the specified amount of hoop material 6 is fed in on the basis of the working pattern 62 a, the working drive instruction component 62 of the feeder controller 29 halts the working feed in step S13.

At this point, the crank angle has reached the crank angle θ2 (see FIG. 6), which is bottom dead center.

As shown in FIG. 10B, the working return operation is an operation of pulling back the hoop material 6 by the amount the hoop material 6 was fed in the working feed operation, on the basis of the working pattern 62 a, from bottom dead center (θ2) up until the point when the pilot pins 16 are removed from the positioning holes 6 a in the hoop material 6.

In step S14, the working drive instruction component 62 of the feeder controller 29 starts pulling back the hoop material 6 by the amount the hoop material 6 was fed in the working feed operation. The working drive instruction component 62 of the feeder controller 29 halts the working return operation in step S15 when the hoop material 6 is pulled back by the amount the hoop material 6 was fed during working drive, on the basis of the working pattern 62 a.

At this point, the crank angle has reached the crank angle θ3 (see FIG. 8).

Next, in step S16, the process drive instruction component 61 pushes the hoop material 6 in the downstream direction X by an amount equivalent to one process, on the basis of the process pattern 61 a. This process feed operation starts at the point (θ3) when the pilot pins 16 come out of the hoop material 6, and ends by the point when the pilot pins 16 are inserted into the hoop material 6 (θ4) in the course of lowering the slide 35.

As shown in FIG. 10C, when the hoop material 6 is fed in by an amount equivalent to one process on the basis of the process pattern 61 a, the process drive instruction component 61 concludes the process feed in step S17, and halts the process feed operation in step S18.

In step S19, the feeder controller 29 determines whether or not the scheduled number of process feeds have been completed, and if the scheduled number of process feeds have not been completed, control proceeds to step S11. Since the slide 35 is descending again, upon reaching the specific crank angle θ4 in step S11, the working feed operation is performed again in step S12. Steps S11 to S19 are repeated in this manner.

Then, in step S19, if it is determined that the feeder controller 29 has ended the scheduled number of process feeds and the scheduled number of products have been manufactured, control is halted.

3. Features, Etc. (3-1)

The leveler feeder 2 (an example of a roll feeder) in this embodiment is a roll feeder that conveys the hoop material 6 to the pressing machine 3, and comprises the paired upper feed roll 23 (an example of a first roll) and lower feed roll 24 (an example of a second roll), the servo motor 25 (an example of a motor), and the feeder controller 29 (an example of a controller). The paired upper feed roll 23 and lower feed roll 24 are disposed so as to clamp the hoop material 6, and feed the hoop material 6 in the conveyance direction. The servo motor 25 drives the upper feed roll 23 and/or the lower feed roll 24. The feeder controller 29 controls the drive of the servo motor 25. The feeder controller 29 has the process drive instruction component 61 and the working drive instruction component 62. The process drive instruction component 61 drives the servo motor 25 so as to feed the hoop material 6 to the pressing machine 3 side in between one press working and the next press working. The working drive instruction component 62 drives the servo motor 25 so as to feed the hoop material 6 to the pressing machine 3 side during press working.

The phrase “during press working” used above indicates that the crank angle shown in FIG. 6 is from θ1 to θ3.

Thus, the upper feed roll 23 and/or the lower feed roll 24 is driven by the servo motor 25 so that the hoop material 6 is fed to the pressing machine 3 side during press working by the pressing machine 3. This suppresses the generation of tension in the hoop material 6 due to a change in pass line when the hoop material 6 sags during press working.

That is, tension can be prevented from being generated in the hoop material 6 during press working by rotating the upper feed roll 23 and/or the lower feed roll 24, without separating the upper feed roll 23 and/or the lower feed roll 24 from the hoop material 6.

Therefore, it is unnecessary to perform a release operation in which the upper feed roll 23 or the lower feed roll 24 is separated from the hoop material during working, and it is only necessary to drive the upper feed roll 23 and/or the lower feed roll 24, so power consumption and the generation of vibration and sound can be reduced.

Also, since there is no need to physically move the upper feed roll 23 or the lower feed roll 24 away from the hoop material 6, the recent demand for higher production speeds can be met.

(3-2)

With the leveler feeder 2 (an example of a roll feeder) in this embodiment, the working drive instruction component 62 drives the servo motor 25 so that the hoop material 6 is fed by a certain amount to the pressing machine 3 side in the descent of the slide 35 of the pressing machine 3 during press working, and so that the hoop material 6 is pulled back by a specific amount from the pressing machine 3 side in the ascent of the slide 35 during press working.

Thus pulling back the hoop material 6 by a specific amount from the pressing machine 3 side in the ascent of the slide 35 allows the position of the hoop material 6 to be restored when the height of the hoop material 6 has returned to its original position during press working.

Also, returning the hoop material 6 to its original position makes it possible to prevent the twisting that results from misalignment of the positions of the pilot pins 16 and the positioning holes 6 a of the hoop material 6, so the hoop material 6 can be prevented from rising along with the upper dies 11.

The “specific amount” is a very small value such as 5 mm, for example.

(3-3)

With the leveler feeder 2 (an example of a roll feeder) in this embodiment, “during press working” is from the point when the pilot pins 16 formed on the upper dies 11 attached to the slide 35 are inserted into the hoop material 6 (θ1), up until the point when the pilot pins 16 are removed from the hoop material 6 (θ3). The working drive instruction component 62 drives the servo motor 25 so that a specific amount of the hoop material 6 is fed to the pressing machine 3 side by the time the slide 35 reaches bottom dead center (θ2) from the point when the pilot pins 16 were inserted into the hoop material 6 (θ1), and so that a specific amount of the hoop material 6 is pulled back from the pressing machine 3 side by the point when the pilot pins 16 are removed from the hoop material 6 (θ3) from bottom dead center (θ2).

Thus, the generation of tension due to descent can be suppressed by feeding a specific amount of the hoop material 6 to the pressing machine 3 side by the point when the slide 35 reaches bottom dead center from the point when the pilot pins 16 were inserted.

Also, the pilot pins 16 can be prevented from catching on the hoop material 6, and the hoop material 6 from rising along with the upper dies 11, by pulling back a specific amount of the hoop material 6 from the pressing machine 3 side by the time the pilot pins 16 are removed from the hoop material 6.

(3-4)

With the leveler feeder 2 (an example of a roll feeder) in this embodiment, the working drive instruction component 62 stores the working pattern 62 a, which indicates the relation between the feed amount of the hoop material 6 and the position of the slide 35 when the hoop material 6 is fed by a specific amount to the pressing machine 3 side, and the relation between the pull-back amount of the hoop material 6 and the position of the slide 35 when the hoop material 6 is pulled back by a specific amount from the pressing machine 3 side. The working drive instruction component 62 drives the servo motor 25 so as to feed the hoop material 6 to the pressing machine 3 side and to pull back the hoop material 6 from the pressing machine 3 side on the basis of the working pattern 62 a.

Because the relation between the feed amount of the hoop material 6 and the position of the slide 35 when the hoop material 6 is fed by a specific amount to the pressing machine 3 side, and the relation between the pull-back amount of the hoop material 6 and the position of the slide 35 when the hoop material 6 is pulled back by a specific amount from the pressing machine 3 side are thus stored, the working drive instruction component 62 can perform feed of the hoop material 6 to the pressing machine 3 side and pull-back from the pressing machine 3 side at the appropriate timing on the basis of the crank angle (position information about the slide 35) transmitted from the pressing machine 3.

(3-5)

The leveler feeder 2 (an example of a roll feeder) in this embodiment comprises the plurality of upper work rolls 21 (an example of a first work roll) and the plurality of lower work rolls 22 (an example of a second work roll). The upper work rolls 21 are disposed on the upstream side of the upper feed roll 23 in the conveyance direction. The lower work rolls 22 are disposed on the upstream side of the lower feed roll 24 in the conveyance direction. The upper work rolls 21 and the lower work rolls 22 are alternately disposed along the conveyance direction.

Any winding curl in the hoop material 6 can be corrected by disposing the upper work rolls 21 and the lower work rolls 22 in this manner.

(3-6)

With the leveler feeder 2 (an example of a roll feeder) in this embodiment, the servo motor 25 drives the upper work rolls 21 and/or the lower work rolls 22.

Consequently, when the upper work roll 21 and the lower work roll 22 are provided, the upper work rolls 21 or the lower work rolls 22 can be rotationally driven along with the upper feed roll 23 or the lower feed roll 24 during press working to feed the hoop material 6 to the pressing machine 3 side.

(3-7)

The leveler feeder 2 (an example of a roll feeder) in this embodiment comprises the separation cylinder 27 (an example of a separation component), the measuring roll 51, and the measuring roll encoder 52 (an example of a roll position sensor). The separation cylinder 27 separates the upper feed roll 23 from the lower feed roll 24. The measuring roll 51 is disposed so as to be in contact with the hoop material 6, and rotates along with the movement of the hoop material 6. The measuring roll encoder 52 senses the position of the measuring roll 51. The feeder controller 29 further has the working pattern generator 74. The working pattern generator 74 generates the working pattern 62 a in which the position of the slide 35 during press working in a state in which the upper feed roll 23 has been separated from the lower feed roll 24 by the separation cylinder 27 is associated with the movement of the hoop material 6, and stores the working pattern 62 a in the working drive instruction component 62.

Consequently, the working pattern 62 a can be generated in which the position of the slide 35 has already been associated with the movement of the hoop material 6 during press working in a state in which the upper feed roll 23 has been separated from the lower feed roll 24, using the dies 10 that will be used.

Therefore, it is possible to feed the hoop material 6 to the pressing machine 3 side or to pull back the hoop material 6 from the pressing machine 3 side at the appropriate timing in the raising and lowering of the slide 35.

(3-8)

The leveler feeder 2 (an example of a roll feeder) in this embodiment further comprises the plurality of upper work rolls 21 (an example of a first work roll) and the plurality of lower work rolls 22 (an example of a second work roll). The upper work rolls 21 are disposed on the upstream side of the upper feed roll 23 in the conveyance direction. The lower work rolls 22 are disposed on the upstream side of the lower feed roll 24 in the conveyance direction. The upper work rolls 21 and the lower work rolls 22 are alternately disposed along the conveyance direction. The servo motor 25 drives the upper work rolls 21 and/or the lower work rolls 22. The separation cylinder 27 separates the upper work rolls 21 from the lower work rolls 22.

Consequently, when the upper work rolls 21 and the lower work rolls 22 are provided, it is possible to find the relation between the position of the slide 35 and the position of the hoop material during press working in a state in which the upper work rolls 21 and the upper feed roll 23 have been separated from the lower work rolls 22 and the lower feed roll 24.

(3-9)

The press system 1 in this embodiment comprises the pressing machine 3 and the leveler feeder 2 (an example of a roll feeder). The pressing machine 3 performs pressing of the hoop material 6. The leveler feeder 2 has the paired upper feed roll 23 (an example of a first roll) and lower feed roll 24 (an example of a second roll), the servo motor 25, and the feeder controller 29 (an example of a controller). The feeder controller 29 controls drive of the servo motor 25. The feeder controller 29 has the process drive instruction component 61 and the working drive instruction component 62. The process drive instruction component 61 drives the servo motor 25 so as to feed the hoop material 6 to the pressing machine 3 side in between one press working and next press working. The working drive instruction component 62 drives the servo motor 25 so as to feed the hoop material 6 to the pressing machine 3 side during press working.

Consequently, there is no need for a release operation in which the upper feed roll 23 or the lower feed roll 24 is separated from the hoop material 6 during working, and it is only necessary to drive the first roll and the second roll, so energy consumption and the generation of vibration and sound can be reduced.

Also, since it is not necessary to physically move the upper feed roll 23 or the lower feed roll 24 away from the hoop material, the recent demand for higher production speeds can be met.

(3-10)

The hoop material conveyance method in this embodiment is a hoop material conveyance method for conveying the hoop material 6 to the pressing machine 3, and comprises a step S16 (an example of a process drive step) and a step S12 (an example of a working drive step). Step S16 (an example of a process drive step) involves driving the upper feed roll 23 and/or the lower feed roll 24 using the servo motor 25 as a drive source, and feeding the hoop material 6 to the pressing machine 3 side in between one press working and the next press working. Step S12 (working drive step) involves driving the servo motor 25 so as to feed the hoop material 6 to the pressing machine 3 side during press working.

Consequently, there is no need for a release operation in which the upper feed roll 23 or the lower feed roll 24 is separated from the hoop material 6 during working, and it is only necessary to drive the first roll and the second roll, so energy consumption and the generation of vibration and sound can be reduced.

Also, since there is no need to physically move the upper feed roll 23 or the lower feed roll 24 away from the hoop material, the recent demand for higher production speeds can be met.

4. Other Embodiments

An embodiment of the present invention was described above, but the present invention is not limited to or by the above embodiment, and various modifications are possible without departing from the gist of the invention.

(A)

In the above embodiment, the working drive operation (the working feed operation and the working return operation) was performed after the working pattern 62 a was obtained in advance by the movement sensor 28, but positions instructions may be issued moment by moment on the basis of feedback information from the tension generated in the hoop material 6, rather than storing information ahead of time. That is, the hoop material 6 is pulled into the dies 10 during working, but if tension increases at that time, the servo motor 25 is controlled so as to bring the tension close to zero.

FIG. 11 is a diagram showing the configuration of a press system 100 comprising a roll feeder 102 in which a torsion sensor 80 is provided on the axis of the lower feed roll 24, as an example of a tension sensor for the hoop material 6.

As shown in FIG. 11, the feeder controller 129 of the roll feeder 102 differs from the feeder controller 29 shown in FIG. 1 in that the working pattern generation instruction component 60, the second switching component 73, and the working pattern generator 74 are not provided. Also, the roll feeder 102 is provided with the working drive instruction component 162 for outputting a position instruction on the basis of the output of the torsion sensor 80. Furthermore, a first switching component 163 does not have d as compared with the first switching component 63 in FIG. 1, and can perform a-b connection and b-c connection.

When the crank angle reaches 81, the working drive instruction component 162 of the feeder controller 129 controls the servo motor 25 so that the torque sensed by the torsion sensor 80 drops to zero until bottom dead center θ2 is reached. When performing the working drive operation, as long as no process drive operation is carried out and there is no pull-in to the dies 10, no torque will be produced at the rolls (the upper feed roll 23, the lower feed roll 24, the upper work rolls 21, and the lower work rolls 22), so it is possible to use a control method involving feedback of this torque.

Thus providing the torsion sensor 80 as a torque sensor and measuring the torque makes it possible to feed the hoop material 6 to the pressing machine 3 side at the appropriate timing in the raising and lowering of the slide 35.

In pulling back the hoop material 6 from the pressing machine 3 side, the hoop material 6 bends, so no pushing force is generated and the tension does not become negative. Therefore, in pullback, the tension should be set at a predetermined weak level at which no problem will occur. That is, in feeding the hoop material 6 to the pressing machine side, the tension may be controlled to be zero, and in pullback of the hoop material 6 from the pressing machine 3 side, control may be performed so that the tension is weak. The term “weak tension” encompasses zero.

The tension sensor for sensing the tension generated in the hoop material 6 is not limited to a torque sensor such as the torsion sensor 80.

(B)

In the above embodiment, the working pattern 62 a was calculated by the movement sensor 28, but the movement sensor 28 may not be provided, and the position (pullback amount) of the hoop material 6 may be calculated for each crank angle. In this case, as shown by the roll feeder 202 in the press system 200 shown in FIG. 12, a feeder controller 229 is provided with a calculator 81, and is not provided with the working pattern generation instruction component 60, the second switching component 73, or the working pattern generator 74. Also, the first switching component 163 does not have d as compared with the first switching component 63 in FIG. 1, and can make an a-b connection and a b-c connection. The calculator 81 can calculate the amount of pullback for each crank angle from the distance in the vertical and horizontal directions between the clamping portion of the upper feed roll 23 and the lower feed roll 24, which are the exit of the leveler feeder 2, and the entrance to the die 10, and the movement of the slide 35 (the relation between the crank angle and the position) after the upper dies 11 make contact with the hoop material 6. This calculation result is stored as the working pattern 62 a in the working drive instruction component 62.

(C)

In the above embodiment, the measuring roll 51 is left in contact with the hoop material 6 during manufacture of the product by the pressing operation, but the measuring roll 51 may be separated from the hoop material 6 by a separating mechanism (not shown).

FIG. 13 is a diagram showing the configuration of a press system 300 having such a leveler feeder 2. With the feeder controller 329 of the press system 300 shown in FIG. 13, compared to the feeder controller 29 shown in FIG. 1, information from the measuring roll encoder 52 is not inputted to the position comparison component 64 via the position calculator 71, and instead the information from the servo motor encoder 26 is inputted via the position calculator 71. The position calculator 71 receives the rotational angle of the motor from the servo motor encoder 26, calculates the position of the hoop material 6 (this can also be referred to as the movement amount (feed amount or return amount) of the hoop material 6), and outputs the position signal to the position comparison component 64.

The position comparison component 64 compares the position signal from the position calculator 71 with the position instruction inputted from the process drive instruction component 61 or the working drive instruction component 62 via the first switching component 63 and the second switching component 73, and the difference is outputted to the position controller 65.

Thus, the feeder controller 329 performs position comparison at the position comparison component 64 using the servo motor encoder 26.

(D)

In the above embodiment, in the generation of the working pattern 62 a, the movement amount of the hoop material 6 for each crank angle during press working was sensed by the measuring roll 51 of the movement sensor 28, but the servo motor encoder 26 may be used to detect the amount of movement.

However, when the movement amount is sensed by the servo motor encoder 26 (semi-closed), feedback is preferably provided with the measuring roll 51 (fully closed) in order to eliminate the influence of slippage between the lower feed roll 24 and the hoop material 6. This is because a large angular velocity is sometimes imparted to the lower feed roll 24 and the upper feed roll 23 in order to deal with large acceleration and deceleration.

(E)

In the above embodiment, the hoop material 6 was pulled back in the working return operation by the amount that the hoop material 6 had been fed in the working feed operation, but it need not be pulled back. In this case, in the following process feed operation, the hoop material 6 may be fed in an amount that is smaller by the amount that the hoop material 6 was fed in the working feed operation.

(F)

In the above embodiment, the upper feed roll 23, the lower feed roll 24, and the lower work rolls 22 were rotationally driven by the single servo motor 25, but two servo motors may be provided, one for the upper feed roll 23 and the lower feed roll 24 and one for the lower work rolls.

(G)

In the above embodiment, the leveler feeder 2 was described as an example of a roll feeder, but the feeder device may not have a leveler function of correcting winding curl in the hoop material 6, and may just feed the hoop material 6. That is, the upper work rolls 21 and the lower work rolls 22 need not be provided.

(H)

In the above embodiment, the feeder controller 29 and the press controller 39 were described separately, but they may instead be combined into a single control device.

(I)

In the above embodiment, the servo motor 25 was used as an example of a motor, but a servo motor is not the only option, and an electric motor, a stepping motor, or a hydraulic motor may be used.

INDUSTRIAL APPLICABILITY

The roll feeder and the hoop material conveyance method of the present invention have the effect of reducing energy consumption and the generation of vibration and sound, and are useful, for example, as a progressive pressing system or the like. 

1. A roll feeder adapted to convey a hoop material to a pressing machine, the roll feeder comprising: a paired first roll and second roll configured to be disposed so as to clamp the hoop material and feed the hoop material along a conveyance direction; a motor configured to drive at least one of the first roll and the second roll; and a controller configured to control drive of the motor, the controller including a process drive instruction component configured to drive the motor so as to feed the hoop material to a pressing machine side in between one press working and next press working, and a working drive instruction component configured to drive the motor so as to feed the hoop material to the pressing machine side during press working.
 2. The roll feeder according to claim 1, wherein the working drive instruction component is further configured to drive the motor so as to feed the hoop material by a specific amount toward the pressing machine side when a slide of the pressing machine is lowered during the press working and pull back the hoop material by the specific amount from the pressing machine side when the slide is raised during the press working.
 3. The roll feeder according to claim 2, wherein “during press working” is from when a pilot pin formed on an upper die attached to the slide is inserted into the hoop material until the pilot pin is removed from the hoop material, and the working drive instruction component is further configured to drive the motor so as to feed the specific amount of the hoop material toward the pressing machine side from a point when the pilot pin is inserted into the hoop material until the slide reaches a bottom dead center and pull back the specific amount of the hoop material from the pressing machine side by a point when the pilot pin is removed from the hoop material from bottom dead center.
 4. The roll feeder according to claim 2, wherein the working drive instruction is further configured to store a working pattern indicating a relation between a position of the slide and a feed amount of the hoop material when the hoop material is fed by the specific amount to the pressing machine side, and a relation between the position of the slide and the feed amount of the hoop material when the hoop material is pulled back by the specific amount from the pressing machine side, and drive motor so as to feed the hoop material to the pressing machine side and pull the hoop material back from the pressing machine side based on the working pattern.
 5. The roll feeder according to claim 1, further comprising a tension sensor configured to sense tension of the hoop material, the working drive instruction component being further configured to control the motor so that the tension sensed by the tension sensor is close to zero when the hoop material is fed toward the pressing machine side during the press working.
 6. The roll feeder according to claim 5, wherein the tension sensor has a torque sensor provided at the axis of at least one of the first roll and the second roll, and the working drive instruction component is further configured to control the motor so that torque sensed by the torque sensor is close to zero during the press working.
 7. The roll feeder according to claim 1, further comprising: a plurality of first work rolls disposed on an upstream side of the first roll along the conveyance direction; and a plurality of second work rolls disposed on an upstream side of the second roll along the conveyance direction, the first work rolls and the second work rolls being alternately disposed along the conveyance direction.
 8. The roll feeder according to claim 7, wherein the motor drives at least one of the plurality of first work rolls and the plurality of second work rolls.
 9. The roll feeder according to claim 4, comprising: a separation component configured to separate the first roll from the second roll; a measuring roll disposed so as to contact the hoop material, the measuring roll being configured to rotate along with movement of the hoop material; and a roll position sensor configured to sense a position of the measuring roll, the controller further including a working pattern generator configured to generate the working pattern in which movement of the hoop material is associated with a position of the slide during the press working in a state in which the first roll has been separated from the second roll by the separation component, and store the working pattern in the working drive instruction component.
 10. The roll feeder according to claim 9, further comprising: a plurality of first work rolls disposed on an upstream side of the first roll along the conveyance direction; and a plurality of second work rolls disposed on an upstream side of the second roll along the conveyance direction, the first work rolls and the second work rolls being alternately disposed along the conveyance direction.
 11. The roll feeder according to claim 10, wherein the motor drives at least one of the plurality of first work rolls and the plurality of second work rolls, and the separation component separates the plurality of first work rolls from the plurality of second work rolls.
 12. A press system, comprising: a pressing machine configured to perform press working of a hoop material; and a roll feeder configured to convey the hoop material to the pressing machine, the roll feeder including a paired first roll and second roll configured to be disposed so as to clamp the hoop material, feed the hoop material along a conveyance direction; a motor configured to drive at least one of the first roll and the second roll; and a controller configured to control drive of the motor, the controller having a process drive instruction component configured to drive the motor so as to feed the hoop material to the pressing machine side in between one press working and next press working; and a working drive instruction component configured to drive the motor so as to feed the hoop material to the pressing machine side during press working.
 13. A hoop material conveyance method adapted to convey a hoop material to a pressing machine, the hoop material conveyance method comprising: driving at least one of a first roll and a second roll with a motor as a drive source and feeding the hoop material to a pressing machine side in between one press working and next press working; and driving the motor so as to feed the hoop material to the pressing machine side during the press working. 